Bio-oils are an important part of the future energy composition. This review primarily focuses on model compounds, catalysts, and equipment involved in the hydrodeoxygenation (HDO) of bio-oils. ...Initially, this article reviews the basic physicochemical properties of bio-oils and introduces different upgrading methods. Among them, HDO can effectively facilitate calorific value and improve the acidity and viscosity of bio-oils. Secondly, the basic HDO reaction pathways and proposed catalytic mechanism of various model compounds are summarized to understand the catalytic behavior and structure-performance relationship of the HDO reaction. Subsequently, we review different catalysts used in actual HDO of bio-oils, some of which lead to excellent stability and improved HDO reactivity. Finally, progress in the development of HDO equipment, including fixed bed and ebullated bed reactors in the pilot stage, is reviewed. This review aims to summarize progress in the utilization of the HDO process and provides useful insights for the efficient practical application of bio-oils.
Bio-oils are an important part of the future energy composition.
Elbow erosion, which is mainly caused by collisions between particles and wall, is a prominent problem encountered in dilute-phase pneumatic conveying systems. The particle shape and air-flow regime ...markedly influence the particle-wall collision characteristics through the ambiguous impacts of both the geometric boundary and relative velocity. This paper numerically investigates the effects of particle shape and swirling intensity on elbow erosion in dilute-phase pneumatic conveying using the CFD-DEM method. Initially, the non-spherical particles are modelled based on polyhedrons and scanned real coal particles, and their morphologies are characterized according to sphericity. Subsequently, the calculation compatibility of attrition models based on CFD-DEM simulation is calibrated by comparing the erosion rates calculated on the basis of different classical models. In addition, the compatibility of the selected model for the coarse particle pneumatic conveying is verified via experimental measurements. Based on the two-way coupled Eulerian-Lagrangian method, simulations of the gas-solid flow that consider the elbow direction, particle shape, and swirling intensity are performed, and the correlation models with sphericity and swirling number for different elbow directions are assessed. In general, it is found that the elbow direction affects the magnitude, distribution, and position of the maximum of the erosion rate. The mean erosion rate generally varies with the particle sphericity in a nearly inclined “S” pattern in all elbow directions. The mean erosion rate evidently decreases with swirling number first quickly and then slowly. To develop a modified predictive model based on the classical erosion model, the polynomial and the Exp3p2 exponential function are adopted to fit the influences of particle shape and swirling intensity, respectively. The fitting deviations agree reasonably well with the calculation results.
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•Mean erosion rates generally vary with particle sphericity in inclined “S” pattern.•Polynomial functions fit the relationship of particles shape and erosion rates well.•Mean erosion rates evidently decrease with the swirling number.•Exponential functions fit the relationship of swirling number and erosion rate well.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Using abandoned oil wells for geothermal power generation can relieve energy problem, save drilling cost, and govern the pollution caused by the residual oil of the abandoned oil wells. In this ...paper, a novel method for enhancing the geothermal utilization efficiency by developing thermal reservoirs is presented. A 2-D thermal reservoirs coupling with 1-D wellbore heat transfer model was set up to simulate geothermal energy production, and the effects of the thermal reservoirs on the geothermal production and electric power output were analyzed. The study results showed that the geothermal well with thermal reservoirs could produce about 4 times the heat and electric power output as that without thermal reservoirs. Moreover, the thermal reservoirs parameters would impact the heat production and power generation significantly. Especially, the heat production and electric power output increased with the thermal reservoirs depth and the fluid injection rate, however increased with the thermal reservoirs length firstly, and then decreased, which indicated that there was a maximal heat production and power generation at an optimal reservoir length. Simultaneously, the fluid loss in the thermal reservoirs increased with the thermal reservoirs depth and length as well as thermal reservoirs porosity.
•A 2-D thermal reservoirs coupling with 1-D wellbore heat transfer model was set up.•The simplified model greatly shortened the simulated calculation time.•The effects of porosity, fluid loss and permeability on production were considered.•The thermal reservoirs could enhance the heat and electric power output observably.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Cervical cancer that relapses after platinum-containing chemotherapy is often refractory to salvage therapy. Cemiplimab, a fully human antibody to PD-1, was compared with single-agent chemotherapy ...with pemetrexed, gemcitabine, irinotecan, topotecan, or vinorelban. Among 608 patients, median overall survival was 8.5 months with chemotherapy and 12.0 months with cemiplimab.
Abstract
Background
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel β-coronavirus, causes severe pneumonia and has spread throughout the globe rapidly. The disease associated ...with SARS-CoV-2 infection is named coronavirus disease 2019 (COVID-19). To date, real-time reverse-transcription polymerase chain reaction (RT-PCR) is the only test able to confirm this infection. However, the accuracy of RT-PCR depends on several factors; variations in these factors might significantly lower the sensitivity of detection.
Methods
In this study, we developed a peptide-based luminescent immunoassay that detected immunoglobulin (Ig)G and IgM. The assay cutoff value was determined by evaluating the sera from healthy and infected patients for pathogens other than SARS-CoV-2.
Results
To evaluate assay performance, we detected IgG and IgM in the sera from confirmed patients. The positive rate of IgG and IgM was 71.4% and 57.2%, respectively.
Conclusions
Therefore, combining our immunoassay with real-time RT-PCR might enhance the diagnostic accuracy of COVID-19.
A peptide-based magnetic chemiluminescence enzyme immunoassay for the detection of SARS-CoV-2 antibodies was developed; 71.4% (197 of 276) and 57.2% (158 of 276) of the COVID-19 inpatients were positive for IgG and IgM against SARS-CoV-2.
This work studied the influence of the particle shape and flow regime on the lump coal breakage in pneumatic conveying using CFD-DEM simulation. A variety of agglomerates with different sphericities ...were modelled by the parallel bond method to analyse the breakage characteristics of lump coal. The numerical parameters, simulation conditions and CFD-DEM simulation results were separately validated by experimentation. To demonstrate the lump coal breakage process, the mechanism energy variation in the coal agglomerate was analysed. The fragmentation degree of the coal agglomerate was positively correlated with the energy difference in collision. The integrality ratio of the coal agglomerate increased with the particle sphericity and swirling number in pneumatic conveying. A quasi-periodical downgrade in the coal agglomerate integrality ratio was shown in the swirling flow. A remarkable improvement in the coal agglomerate integrality ratio from approximately 0.85 to 0.975 was observed in swirling flow pneumatic conveying. The regression relationship of the particle sphericity and swirling number fit the Exp3p2 exponential function well.
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•Obtained a real morphology of lump coal agglomerate by parallel bond model•Analysed the coal agglomerate breakage in sight of mechanism energy variation•A quasi-periodic integrality ratio downgrade was shown in the swirling flow.•The integrality ratio increased with particle sphericity and swirling number.•Exponential function fits particle shape and swirling intensity influence well.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The present investigation aims at developing a gas and particle flow model based on CFD-DEM coupling for three types of swirling generators. Grid and time size dependence tests were performed to ...validate the numerical model; the prediction ability of the model was confirmed through comparison with experimental data. Detailed studies of certain parameters (including the fluid pattern, swirling number and pressure drop) were based on the CFD method for the three-lobed, rifle and internal spiral vanes swirling generator pipelines. These studies were performed using dimensionless forms and numerical simulations. The peak regions of the axial velocity for the three-lobed and internal spiral vanes pipes have obvious asymmetrical patterns that rotate quasi-periodically downstream; the three-lobed pipe generates the largest swirl number and decays the fastest. In addition, quantitative calculations using the CFD-DEM coupling model, which include the particle distribution and the pneumatic conveying efficiency, suggest that the three-lobed swirling generator is suitable for the preliminary conveying stage and that the internal spiral structure in this work is a favorable option for swirling pneumatic conveying systems for coarse particles.
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•A quasi-periodical and asymmetrical rotating pattern in swirling flow•The three-lobed pipe has induced the largest swirl number in the three objects.•The particle dispersity increasing with inlet velocity and swirling intensity.•The three-lobed swirling generator is suitable for startup of conveying.•The internal spiral swirling generator is fit for the stabilization conveying.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
In this paper, abandoned “dry hole” oil wells are simulated as a source of geothermal power for generating electricity. Isobutane is chosen as the working fluid. It is heated by the geothermal energy ...from geologic formation and drives the turbine to generate electricity. A model based on transient formation heat transfer is presented. Furthermore, a numerical simulation for an abandoned well with a depth of 6000 m is performed. The result shows that the outlet temperature of fluid leaving the recovery well gradually decreases with the system operating time increasing and ultimately approaches stability. The stabilized time of the system can be shortened by either the increasing formation thermal conductivity or the decreasing inlet velocity of fluid entering the injection well but is not significantly influenced by the formation heat capacity. The net power depends on the total obtained heat and the outlet temperature of fluid leaving the recovery well. And increasing the inlet velocity can increase the total obtained heat but lower the fluid outlet temperature. Consequently there is an optimal inlet velocity of fluid entering the injection well to maximize the net power for a specified geothermal heat source.
•Electricity generation using geothermal energy from an oil well "dry hole" is simulated.•A geothermal power generation model based on transient formation heat transfer is presented.•The factors that affect stabilized time and performance of the system are investigated.•There is an optimal inlet velocity of fluid entering the injection well to maximize the net power.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
A three-dimensional thermal-hydrologic model considering water losses was developed to simulate heat extraction from an enhanced geothermal system (EGS), consisting of an injection well, a production ...well, a reservoir and the surrounding formation. The model was verified by application to Fenton Hill EGS. Based on the model, the influences of some factors on heat extraction were analyzed. As surrounding formation permeability increases, there are more water losses from the reservoir to the surrounding formation, leading to decreased heat extraction rate. When the two wells approach the edge of the reservoir, heat extraction is restrained, indicating that the two wells should be located about 20–25 m from the edge of the reservoir. Enlarged reservoir volume would not efficiently enhance heat extraction with fixed well layout, suggesting that well layout should be further optimized. Optimized open-hole length is equal to vertical reservoir dimension. Lower production pressure enhances heat extraction, resulting from increased production flow rate and decreased water loss rate. For each factor, it is concluded that thermal breakthrough time mainly depends on production flow rate and water loss rate, showing the important effect of water losses. The results of this paper can offer some suggestions to optimize the EGS performance.
•As surrounding formation permeability increases, heat extraction rate decreases.•When the two wells approach the edge of the reservoir, heat extraction is restrained.•Enlarged reservoir volume would not enhance heat extraction with fixed well layout.•Open-hole length is optimized, and low production pressure enhances heat extraction.•Thermal breakthrough time mainly depends on production flow rate and water loss rate.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
During 2018-2020, we isolated 32 Eurasian avian-like swine influenza A(H1N1) viruses and their reassortant viruses from pigs in China. Genomic testing identified a novel reassortant H3N1 virus, which ...emerged in late 2020. Derived from G4 Eurasian H1N1 and H3N2 swine influenza viruses. This virus poses a risk for zoonotic infection.
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DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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